Generally speaking, this invention relates to an arterial catheter placement assembly. More particularly, this invention relates to such an assembly which provides ease of insertion and placement of the distal end of the catheter in the blood vessel of a patient in the desired location. That is, the assembly includes a combination needle and guide tube, both of which pass through the lumen of the catheter and extend slightly out the front end thereof prior to use. The assembly includes a guide tube slide mounted on the proximal end of the guide tube for controlling the advance and retraction of the guide tube in the assembly of the invention.
In the insertion and placement of a catheter, it is most important to ease as much as possible the movement through the skin of the patient and into the blood vessel. This is important not only from the standpoint of reducing the amount of pain entailed in such a procedure, but also in precise placement of the distal end of the catheter without any undue movement or experimentation.
In the past, placement assemblies of the kind discussed herein have included a guidewire which extends through the needle for providing a "track" for the movement of the catheter into its desired position in the blood vessel of a patient. Representative of such arrangements include, for example, U.S. Pat. No. 4,417,886 which teaches a catheter introduction set utilizing the combination of a needle and guidewire. In such an arrangement, the needle sharpened distal point is utilized to make an introduction through the skin of a patient and into the blood vessel thereof. Thereafter, the guidewire is moved forward through the blood vessel of the patient to the position where the distal end of the resulting catheter is desired. Then, the catheter is moved forward over the guidewire into the desired location. Once this takes place, the guidewire and needle are withdrawn. However, because of the flexibility of the guidewire itself, the actual positioning of the guidewire in the blood vessel may be somewhat tentative, simply because of lack of control of the movement of a wire.
With this invention by contrast, a combination needle and guide tube assembly are provided. That is, the needle and guide tube are positioned coaxially with the catheter and pass through the lumen thereof. The needle, in turn, passes through the lumen of the guide tube. In the initial positioning of the placement device of the invention here, the distal end of the needle extends slightly out of the distal end of the guide tube which in turn extends slightly out of the distal end of the catheter. Positioned on the rear end of the guide tube is a guide tube slide arrangement with a slide handle for manipulating the advancement and retraction of the guide tube.
Thus, the user inserts the needle through the skin of the patient and through the wall of the blood vessel under consideration. Thereafter, blood vessel entry is indicated in the transparent hub of the needle. Then, using the slide arrangement for the guide tube, the operator may advance the guide tube through the desired path in the blood vessel for providing a final path for positioning the distal end of the catheter. Subsequent to this controlled advancement of the guide tube, the catheter is advanced following the path initiated by the guide tube.
After this procedure has taken place, the guide tube and the needle may be withdrawn so that the catheter hub may be connected to appropriate equipment for blood draw, blood transfusion or the delivery of fluids or drugs.
As will be understood by practitioners-in-the-art, the entire circumferential extent of the catheter is guided by the guide tube path for insertion of the catheter to the precise location desired. Control is much more precise than is the case with use of a wire as a guide.
U.S. Pat. No. 3,825,001 teaches a catheter placement arrangement utilizing a guide tube. However, the guide tube assembly is locked in place on the proximal end hub of the catheter. There is no free manipulation of the guide tube to advance it forwardly and to withdraw it. It is simply removed from the hub of the catheter once placement has taken place.
With this invention, by contrast, the guide tube assembly with the slide control arrangement for placing the guide tube and withdrawing it includes a cooperating male luer lock connection which cooperates with the female luer lock connection of the catheter hub for ease of assembly and removal once placement has taken place. Nevertheless, the slide here provides guided advance for precise positioning of the catheter.